



L. W. STORM April 10, 1951 JAR 3 Sheets-Sheet 1 Original Filed March 18, 1947 L. W. STORM April 10, 1951 JAR Original Filedwarch 18, 1947 3 Sheets-Sheet 2 April 10, 1951 1.. w. STORM 7 Re. 23,354

JAR

Original Filed March 18, 1947 3 Sheets-Sheet 3 Reissued Apr. 10, 1951 J AR Lynn W. Storm, Houston, Tex. Original No. 2,499,695, March/7, 1950, Serial No.

735,398, March 18, 1947.

Application for reissue April 24, 1950, Serial No. 157,785

3 Claims. (01. 255-27) Matter enclosed in heavy brackets appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates theadditions made by reissue This invention relates to a jar.

In carrying on well drilling operations tools, or pipe, often become stuck in the well bore and must be removed. At times in carrying on this work, it is desirable to employ a special tool, commonly known as a jar, whereby a blow, or blows, may be delivered to the stuck object thus eventually jarring the'same loose.

A common type of jar now in use is what is known as the mechanical torque type which, in order to operate, must be subjected to considerable torque. This act of imparting torque often presents a considerable hazard and requires additional rigging. Due to friction of surface equipment under high torsional stress the pull to which the stuck object is subjected cannot be accu-' rately ascertained. Therefore, a type of straight pull jar is preferable to the torque type.

Hydraulic jars are also in use but some of these are limited as to their effectiveness in striking a blow by the available hydrostatic pressure of There are also other types of hydraulically actuated jars but they are limited in either their direction of action or in the absence of provision for controlling the intensity of the strokedelivered.

Therefore, it is an object of the present invention to provide a jar of the character described which is of the straight pull type, which can jar either up or down and which can be controlled in operation to deliver blows of varying intensity.

In one form of the invention provision is also made to limit the intensity of the pressure to which the liquid in the barrel may be subjected.

Other objects and advantages will be apparent from the following specification which is illustrated by the accompanying drawings, wherein- Figure 1 is a longitudinal, sectional view of the upper end of the jar.

Figure 2 is a longitudinal, sectional view of the lower end thereof.

Figure 3 is a cross-sectional View taken on the line 3-4 of Figure 2.

Figure 4 is a cross-sectional view taken on the line 4-4 of Figure 2.

Figure'5 is a cross-sectional view taken on the line 5--5 of Figure l.

Figure 6 is a longitudinal, sectional view of the of the lower end thereof.

, Figure8 is a side elevation of the complete tool, partly in section, showing the parts'in an intermediate position between strokes. I

Referring now more particularly to the draw-v ings wherein like numerals of reference designate the same parts in each of the figures, the numeral I designates a string of drill pipe having-a pin at its lower end which may be threaded into the upper end of a tubular barrel 2'. Connected 'to the lower end of the barrel there is a tubular body preferably formed of upper and 1ower'sections3and4. Working axially through the body there is 'a tubular piston stem 5 and its lower end is threaded into a tubular coupling 6 to which any suitable type ofrg rapple 1 may be attached.

The piston stemextends up through the barrel and threaded onto its upper end there is a wash pipe 8 which extends up into the barrel 2.

This piston stem 5 and wash pipe 8 move a unit which is sealed with the lower end of the barrel 2 by the annular seal rings 9 between them and with the lower end of the bodyby means'of the seal rings in between them,

The upper end of the piston stem 5'is enlarged in external diameter, as shown in Figure 5, forming a piston head 5a and mounted on saidhead, beneath the lower end of the wash pipe 8 there is a piston II. of replaceable packing material and isseated on a shoulder l2 of the piston head and is clamped termesh with similar internal longitudinalribs,

or splines, IS in the upper end of the lower body section 4. These splines allow relative longitudi-- nalmovement between the piston stem and body but prevent their relative rotation. 1 e Within the upper body section 3 there is a re.- placeable cylinder l1 whose lower end is seated on an inside annular shoulder la in the body section 3. This cylinder is held in position by means of a sleeve-like retainer 19 which is fitted This piston H is preferably formed into the upper body section 3, whose lower end abuts the upper end of the cylinder I! and whose upper end abuts the lower end of the barrel 2.

The piston II. is of an outside diameter to fit snugly within the: cylinder I! as it passes therethrough but, it is to be noted that the inside diameter of the cylinder I1 is somewhat less. than the corresponding inside'diameter of the portion of the tool the lower end 25 of the body of the tool strikes a blow against the upper end 26 of the coupling 6 which is transferred directly through the grappling tool I to the stuck pipe.

. The emtentand location of the restricted portion in the fluid chamber, prom'did'by the member .17 may, of course, be varied toc'onform to body of the tool so that the cylinder forms a- 1 restriction of limited. extent within the fluid chamber. Therefore, when the piston l l is either above or beneath the cylinder I1 there will be a continuous cylindrical chamber 2'!) above and beneath the cylinder 11 within the body which is completely filled with a suitable fluid. such as heavy oil.

Obviously any attempt to force the piston through the cylinder H in either direction wilIbe' opposed by the liquid, which is substantially non-compressible. Therefore, to allow movement of the. piston through the cylinder the duct I4 has been provided whose lower end emerges. into a longitudinal groove -'2l in the pistonstem head. This duct may be made of a. capacity .to suit as a tapered tap which may be screwed into the .stuck object by rotation of the tool. As illussubstantially non-compressible no relative travel results between the cylinder and. piston except that provided by the transfer of fiuid from the lower to the upper side of the piston through the duct I4. A. certain period of time depending on the pressure: created will be required, therefore, for the cylinder IT to move over the piston and this length of-time is known to the operator.

During this time interval, the operator places a predetermined tension. on the string of pipe I thus imparting a stretch to the pipe and. holds the pipe under this tension until the necessary fluid exchange due to pressure differential takes place.

At the instant the cylinder ll moves completely ofi of the piston the compressive, or restraining, force is lost and the stretched pipe rebounds thus causlng the upper ends 23' of the'splines [6 of the lower body section 4 to strike the lower end 24 of the piston head, as shown in Figures 6 and 7, thus imparting a violent blow whichis transmitted through the piston stem 5 to the stuck pipe 22.

The tool is then in a position to strike downwardly if it be desired to doso. Since the piston is now below the cylinder t1 the operator may sim'plyslack ofi as much weight as he desires and the process of compression and bleed-off above described is repeated, only the compression and the body of the tool, relative tothe anchored the particular conditions under which the jar is constructed to be operated.

Itis. to be here noted that the displacement of the wash pipe 8 and stem 5 are so proportioned that the fluid system is balanced above and beneath the cylinder ll. Thus the fluid is merely transferred from one side of the piston to the other in the complete cycle.

Some of the ribs I5 have longitudinal passageways l5a to allow the free passage of liquidduring the operation of the tool.

The force of either the up or down stroke may be increased or decreased at will by merely regulating the tension. on. the pipe in a given time cause the fluid to leak. through from below to above the piston without a reserve supply of tension on the pipe to cause sufficient stretch to cause a stroke and similarly in slacking off only a sufficient weight may be provided to cause a transfer of liquid from above the cylinder to the chamber beneath thus. avoiding the creationof excessive pressures to the fluid which would cause an accumulation of stretch, or load, on the pipe.

The hydraulic action described is entirely independent of hydrostatic pressures existing in the well fluid. I

It is further to-be noted that circulation may be maintained through the tool at all times as provided by the tubular wash pipe and the bore 2'! which leads through the piston stem, the coupling 6 and the grapple I.

It isobvious that the duct l4 may be dispensed with by leaving a, slight clearance between the piston II and thecylinder H, the cross-sectional 7 lower end and an inside annular shoulder 33 at its upper end.

The seat 30 is controlled by a downwardly opening valve 34 which is normally maintained closed by acoil spring 35' which is seated on the shoulder 3 The seat'32 is controlled by a valve 36 which is normally held closed by a coil spring 31- which is seatedagainst the inside shoulder 33.-

Normally the springs 35 and 31 are of sufiicient strength to hold the corresponding valves closed during the normal operation of the tool, allowing only a sufficient amount of liquid to pass to permit the piston to move through the cylinder; or thevalves may beheld completely closed provided there is a suflicient clearance left between the piston and cylinder to allow the piston to gradually move through the cylinder. However, if a sudden unusual strain were taken to make an up stroke, without the release valve 35, the pressure on the liquid beneath the piston might become sufiiciently high to burst the barrel but in such case with said valve the spring 31 is only of such strength as to withstand a normal safe pressure and in case of excessive pressure the valve 36 would open to relieve the excess pressure; or in making a down stroke if the string of pipe is suddenly-and inadvertently released, without the valve 34 the liquid in the chamber 20 above would be subjected to an abnormally high pressure; but'with the valve 34 the pressure will be relieved thus preventing injury to the tool.

In some cases it may be desired to make only up strokes and in such case the spring 35 is made weak so that when the operating string is moved downwardly the liquid above the piston may readily pass down beneath it without any substantial resistance being ofiered to the piston, and vice versa.

The drawings and description are illustrative merely while the broad principle of the invention will be defined by the appended claims.

What I claim is:

[1. A Well tool comprising inner and outer telescopically arranged tubular parts movable 2;

longitudinally relative to each other, means for connecting said outer part to an operating string, means for connecting said inner part to an object stuck in a well bore, an annular fluid chamber formed between the inner tubular part and the outer tubular part, a piston on the inner tubular part, sealing means at the ends of said chamber, said chamber having a restricted internal diameter intermediate its ends forming a cylinder coacting with said piston to permit of the latter moving through and beyond said cylinder in either direction upon relative longitudinal movement of said inner and outer parts, said cylinder and piston coacting to permit of fluid flow from one side of said piston to the other side thereof as the piston moves through the cylinder, said sealed ends of said chamber being of substantially the same diameter to provide uniform chamber volume regardless of the relative positions of said inner and outer parts, and coacting impact faces on the inner and outer parts arranged to contact when the parts reach the limit of their movement relative to each other in either direction] [2. A well tool comprising inner and outer telescopically arranged tubular parts movable longitudinally relative to each other, means for connecting said outer part to an operating string, means for connecting said inner part to an object stuck in a well bore, an annular fluid chamber formed between the inner tubular part and the outer tubular part, a piston on the inner tubular part, a duct in said piston leading from the upper to the lower end thereof, sealing means at the ends of said chamber, said chamber having a restricted internal diameter intermediate its ends forming a cylinder coacting with said piston to permit of the latter moving through and beyond said cylinder in either direction upon relative longitudinal movement of said inner and outer parts, said cylinder and piston coacting to permit of fluid flow through said duct from one side of said piston to the other side thereof as the piston moves through the cylinder, said sealed ends of said chamber being of substantially the same diameter to provide uniform chamber volume regardless of the relative positions of said inner and outer parts, and coacting impact faces on the inner and outer parts arranged to contact when the parts reach the limit of their movement relative to each other in either direction] [3. A well tool comprising inner and outer telescopically arranged tubular parts movable longitudinally relative to each other, means for connecting said outer part to an operating string, means for connecting said inner part to an object stuck in a well bore, an annular fluid chamber formed between the inner tubular part and the outer tubular part, a piston on the inner tubular part, sealing means at the ends of said chamber, said chamber having a restricted internal diameter intermediate its ends forming a cylinder coacting with said piston to permit of the latter moving through and beyond said cylinder in either direction upon relative longitudinal movement of said inner and outer parts, the annulus of said piston bein spaced from said cylinder to permit of fluid flow around said piston from one side to the other side thereof as the piston moves through the cylinder, said sealed ends of said chamber being of substantially the same diameter to provide uniform chamber volume regardless of the relative positions of said inner and outer parts, and coacting impact faces on the inner and outer parts arranged to contact when the parts reach the limit of their movement relative to each other in either direction] 4. A well tool comprising inner and outer concentrically arranged tubular parts movable longitudinally relative to e ch other, means for connecting one of said parts to an operating string, means for connecting the other of said parts to an object stuck in a well bore, said parts forming a closed fluid chamber, said inner part extending completely through the closed chamber, a piston on the inner part, sealing means on the outer part at each end of said ch mber through which said inner part extends, said outer part having three adjacent sections of unequal internal diameter extending longitudinally of the chamber, wherein the central section is of lesser intern l diameter than the two outer sections and forms a cylinder through which said piston is adapted to move in either direction upon relative longitudinal movement of said inner and outer parts, the annulus of the piston being slightly smaller than said internal cylinder diameter to permit of fluid flow from one side of said piston to the other side thereof as the piston moves through the cylinder, the internal diameters of said sealing means being substantially the same to provide uniform chamber volume regardless of the relative positions of said inner and outer parts, and coacting impact face on the inner and outer parts arranged to contact when the parts reach the limit of their movement relative to each other in either direction,

5. A well tool comprising inner and outer concentrically arranged tubular parts movable longitudinally relative to each other, means for con necting one of said parts to an operating string, means for connecting the other of said parts to an object stuck in a well bore, said parts forming a closed fluid chamber, said inner part extending completely through the chamber, a piston on the inner part, said piston having a duct leading from the upper to the lower end thereof, sealing means on the outer part at each end of said chamber through which said inner part extends, said 7 chamber having a portion of reduced internal diameter between its ends in which the piston is adapted to move upon relative longitudinal movement of said inner and outer parts, said piston being of a size to substantially close said portion to cause a flow of fluid through said duct from one side of the piston to the other side thereof as the piston moves in said portion, the internal diameters of said sealing means being substantially the same to provide uniform chamber volume regardless of the relative positions of said inner and outer parts, and coacting impact face on the inner and outer p rts arranged to contact when the parts reach the limit of their movement relative to each other in either direction.

6. A well tool comprising inner and outer concentricallg arranged tubular parts movable longitudinally relative to each other, means for connecting one of said parts to an operating string, means for connecting the other of said parts to an object stuck in a well bore, said parts forming a closed fluid chamber, said inner part extending completel through the chamber, a piston on the inner part, sealing means on the outer part at each end of the chamber through which said inner part extends, said chamber having a portion of reduced internal diameter between its ends in which the piston is dapted to move upon relative longitudinal movement of said inner and outer parts, the annulus of the piston being slightly smaller than said portion of reduced internal diameter to permit of fluid flow from one 8 side of the piston to the other side thereof as the piston moves in said portion, the internal diameters of said sealing means being substantially the same to provide uniform chamber volume regardles's of the relative of said inner and outer parts, and coacting impact faces on the inner and outer parts arranged to contact when the parts reach the limit of their movement relative to each other in either direction.

10 LYNN W. STORM.

REFERENCES CITED The following references are of record in the file of this patent or the original patent:

UNITED STATES PATENTS Number Name Date 1,401,111 Sigel Dec. 20, 1921 1,578,148 Lissen Mar. 23, 1926 1,584,884 Merrick May 18, 1926 1,637,505 Wigle Aug. 2, 1927 1,804,700 Maxwell 1 May 12', 1931 2,029,579 McCullough Feb. 4, 1936 2,077,760 Knoerr Apr. 20, 1937 2,172,480 Osmun Sept. 12, 1939 2,309,872 Shafier et a1. Feb. 2, 1943 2,474,459 Beck June 28, 1949 FOREIGN PATENTS Number Country Date 399,700 France Apr. 29, 1909 

